WASHINGTON  The Republican National Committee tapped a $5 million line of credit Tuesday as part of a renewed effort to help GOP senators facing re-election difficulties, the party's chairman said Tuesday.

Robert M. "Mike" Duncan said the party committee gave $2 million to the cash-strapped National Republican Senatorial Committee for use in the days before the Nov. 4 elections. The RNC also was spending $3 million in coordination with several Senate Republican campaigns, he said.

Republican-held seats have become increasingly competitive since the GOP national convention in early September, Duncan said.

"Unfortunately we had a downturn with the economic situation in the country and that appeared to put more of the seats in play," he said.

Of the endangered Republican seats, Duncan said the RNC was especially watching contests Kentucky, Georgia, Mississippi, Minnesota, New Hampshire, Oregon and North Carolina. The Democratic Senatorial Campaign committee has been aggressively spending in those states in hopes of solidifying party control of the Senate. Duncan did not volunteer any mention of the race in Alaska, where Republican Sen. Ted Stevens, convicted Monday on seven felony charges, faced an uphill fight to retain his seat.

As of Sunday, the DSCC had spent $53.2 million on independent expenditures for Senate candidates compared to the NRSC's $27.4 million, according to the Campaign Finance Institute, which tracks campaign money.

Duncan said the money spent on Senate races would not undercut the party's spending to help Republican presidential nominee John McCain. So far, the party has spent about $100 million on McCain through various means, including more than $50 million on independent ads, $19 million in coordinated costs and nearly $30 million on combined party-McCain ads on radio and television.

Democrats now control the Senate 51-49, including two independents who vote with them. Democratic Party officials have spoken optimistically about the possibility of achieving a 60-40 majority -- a crucial threshold that would give Democrats greater control over legislation. It takes 60 votes in the Senate to halt debate, a rule that whoever is in the minority regularly uses to stop or alter Senate bills.

Duncan said such an advantage would be akin to the margin President Lyndon B. Johnson enjoyed in the 1960s when the White House succeeded in getting Congress to pass his Great Society programs.

Keeping Democratic victories to a minimum, he said, "means that we don't go back to 1964."

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